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BL Lacertae: Hard Optical Spectrum and GeV γ-ray Emission

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Chinese Journal of Astronomy and Astrophysics 2004年第3期4卷 231-246页

作者： Shan-JieQian Xi-ZhenZhang T.P.Krichbaum NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 Max-Planck-institutfürRadioastronomie AufdemHügel6953121BonnGermany

The spectral energy distribution (SED) of the γ-ray flare observed inJuly 1997 in BL Lacertae is re-considered. It is pointed out that the optical observa-tions made by Webb et al. showed the associated optical flare has a hard spectrum(the average spectral index αopt～ 0.48, F_v∝v^(-α)), and the ASCA observationsmade by Tanihata et al. showed very steep spectra in the soft X-ray band (0.7-1.5 keV) (α_x～3-4). We find that the flux densities and spectral indices in both theoptical and soft X-ray bands are closely consistent with a ‘canonical' synchrotronspectrum emitted by relativistic electrons of a power-law energy distribution witha high energy cutoff, and thus the peak of the SED of the synchrotron radiation (inrepresentation of vF_v) is located in the EUV -- soft X-ray bands. Therefore, theGeV γ-ray emission observed in the July 1997 outburst may be mainly due to thesynchrotron self-Compton (SSC) process, contrasting with the current explanationsin terms of external radiation Compton (ERC) process, in which the seed photonsare mostly taken to be the UV emission from the clouds of the broad emission lineregion. We argue that the hard optical spectra observed during the γ-ray outburstmay be an important signature for the acceleration of high energy electrons (γ_e～10~4)in the γ-ray emitting region.

关键词： galaxies:compact gamma rays:observations quasars:individual:BL Lacertae

Pyrolysis of EVA and its application in recycling of photovoltaic modules

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Journal of Environmental Sciences 2004年第6期16卷 889-893页

作者： ZENGDe-wen ManfredBorn KarstenWambach institutfürEnergieverfahrungstechnikundChemieingenieurwesen TUBergakademieFreiberg09599FreibergGerman DeutscheSolarAG Affred-Lange-Str.1809599FreibergGermany

The basic pyrolysis behaviour of ethylene vinyl acetate(EVA) copolymer, which is often used as a lamination agent in solar modules, was investigated in thermogravimetry, differential thermal analysis(DTA) and thermovolumetry. The TG analysis showed that the EVA pyrolysis can be accelerated under the partial oxidizing atmosphere but the end pyrolysis temperature must be higher than in nitrogen, to eliminate the coke formed. Meanwhile, a strong exothermal peak occurs at about 450℃ under the air condition and gets weaker obviously at the oxygen content lower than 10 vol.%. The mass balance of EVA pyrolysis was given through the thermovolumetry with the output of 10 wt.% permanent gas, 89.9 wt.% condensate and 0.1% residual coke. Besides, the composition of the permanent gas and condensate at different pyrolysis stages were analysed and interpreted on the known pyrolysis mechanism.

关键词： pyrolysis EVA kinetic recycling

Mining and geological knowledge during the Neolithic： a geological study on the variscite mines at Gavà, Catalonia

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Episodes 2003年第4期26卷 295-301页

作者： AntoniCamprublí Joan-CariesMelgarejo JoaquínA.Proenza FidelCosta JosepBosch AlíciaEstrada FerranBorell NikolaiP.Yushkin ValentinL.Andreichev CentrodeGeociencias UniversidadNacionalAut6nomadeM6xico.CarreteraQro.-S.L.P.km15.5CampusUNAM-Juriquilla76230SantiagodeQuerétaroMexico DepartamentdeCristal.lografia MineralogiaiDipbsitsMinerals.FacultatdeGeologia.UniversitatdeBarcelona.MartfiFranquèss／n08028Barcelona（Catalonia）Spain institutfürgeologie MineralogieundGeophysikRuhr-UniversitǎtBochum44780BochumGermany MuseudeGave PlaàaDolorsClua13-1408850Gavà（Catalonia）Spain InstituteofGeology KomiScienceCentreRussianAcademyofSciencesUralDivision.54PervomaiskayaSt.167610Syktyvkar（KomiRep.）RussianFederation

The Gavd Neolithic Mining Complex (GNMC) near Barcelona was active during the Neolithic age, since ca. 6000 BP until about 700 years after. These mines show up to five different underground mining levels, developed as galleries and chambers, communicated through pits, drawing a complex network with a total known length of over 1000 m. These are some of the oldest underground mines in Europe but, contrary to the rest of the mine workings known of the same epoch, this is the only mining complex reported to date whose aim was not mining for conventional substances for the epoch such as chert, ochre or copper. The main aim of the GNMC was variscite, a green phosphate mineral similar to turquoise that can be easily cut and polished to make ornaments such as necklaces or bracelets. This paper is focused mainly on the geological mapping and examination in surface and underground exposures of the different phosphate mineralization types(stratabound and veins) and other relevant geological features such as discordances, thrusts, faults, and folds.

关键词：采矿地质学磷铝石矿新石器时代巴塞罗那加太罗利亚

Discovery of Five Narrow-Line Seyfert 1 Galaxies and Im- plications on the NLS1 Model

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Chinese Journal of Astronomy and Astrophysics 2003年第5期3卷 423-430页

作者： Jiang-HuaWu Xiang-TaoHe YangChen WolfgangVoges NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 DepartmentofAstronomy BeijingNormalUniversityBeijing100875 Max-Planck-institutfürExtraterrestrischePhysik D-85740GarchingGermany

We report the discovery of five Narrow-Line Seyfert 1 galaxies (NLSls) identified from the ROSAT All-Sky Survey bright sources. One of them has a quasar-like luminosity and two, including the quasar-like one, have close companions and/or show interacting features. We calculate the central black hole masses and Eddington ratios for the five NLSls. In combination with the objects of Kaspi et al., we find that NLSls have smaller central black hole masses and higher accretion rate than normal Seyfert 1s.

关键词： black hole physics - galaxy: active - galaxy: Seyfert - X-ray: galaxy

Possible seismic reflector in the lower crust: Evidence from fabrics and experiments of seismic velocity on layered gabbro at high temperature and high pressure

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Chinese Science Bulletin 2003年第9期48卷 914-920页

作者： OUXingong JINZhenmin JINShuyan H.Kern GraduateSchool ChinaUniversityofGeosciencesWuhan430074China FacultyofEarthSciences ChinaUniversityofGeosciencesWuhan430074China institutfürGeowissenschaften UniversitǎtKiel24098KielGermany

Lattice preferred orientations (LPO) of plagioclase and augite are measured on layered gabbro from the Panxi region, Sichuan Province. The LPO concentration [010] of plagioclase and [100] of augite are perpendicular to the foliation, which indicates a kind of growth fabric associated with crystallizing habits of minerals when the magma is solidifying under the compaction. Calculated seismic velocities based on LPO data of minerals give rise to rather strong anisotropy 5.81% and 5.54% for compressional seismic wave (Vp) and shear seismic wave (Vs), respectively. The experiments at high temperature and high pressure show that the P-wave velocity of layered gabbro is 6.44-6.97 km/s with the maximum Vp anisotropy 5.22% and the Poisson's ratio is between 0.28-0.31. According to the comparison of fabrics with seismic velocities of layered gabbro, it is uggested that the large-scale layered intrusive body or the similar layered geological body may exist in the lower crust of this area. Such a layered intrusive body which has strong seismic anisotropy may be the seismic reflector in the lower crust.

关键词：地震反射体地震速率分层辉长石高温高压实验下层地壳格子首选方向各向异性地球物理勘探

Helium,Neon,and Argon in the Iron Meteorites Dongling,Nantan and Ningbo

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Acta Geochimica 1986年第4期5卷 320-330页

作者： H.W.WEBER O.BRAUN F.BEGEMANN Max-Planck-institutfür Chemie Saarstraβe 23 D-6500 Mainz. F. R. C.

The light noble gases He, Ne and Ar have been measured in the iron meteorites Dongling, Nantan andNingbo. Dongling and Ningbo show a deficit of cosmic-ray that produced;He of ca. 30% and 10%,respectively, which is argued to be caused by the loss of;H （tritium） from the meteoroids during the time oftheir exposure to the cosmic radiation. Nantan has the lowest eontent of noble gases as yet reportcd for anyiron meteorite. Cosmogenic;He and;Ar are only about 1/5000 of those in Dongling which has particularlyinteresting implications if the two meteorites belong to the same fall. In addition, Nantan contains non-spallogenic;He which we believe to be of radiogenic origin. This radiogenic;He, together with a U-content of2.6×10;g/g yields a;He retention age close to the cosmic-ray exposure age of Dongling. If Donglingand Nantan were part of the same meteoroid, this result would indicate that He retention in the meteoroidstarted only at or after onset of the exposure to the cosmic radiation. On the other hand, if the He retentionage were 4,500 Ma, a U-content of less than 7.2×10;g/g is required to explain the non-cosmogenic;Hepresent. An upper limit to the number of transuranium or superheavy-element atoms which have deeayed byx-emission in Nantan since onset of He retention is 2×10;per gram.

关键词： Helium,Neon,and Argon in the Iron Meteorites Dongling,Nantan and Ningbo

CCD器件空间滤波在微粒运动速度检测上的应用

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仪器仪表学报 2000年第2期21卷 211-214页

作者：董正超 Klaus Michel Swen Bergeler Klaus Christofori Heinrich Krambeer 山东矿业学院济南分院济南250031 institutf.AllgemeineElektrotechnik ASTECH GmbH

本文报道了基于空间滤波法对变加速运动物体表面运动速度进行实时测量的实验研究。采用 CCD线阵同时作为空间滤波器和光电转换器件。由 CCD线阵实现的差分栅式空间滤波器不仅消除了零频分量对低速运动测量的不利影响 ,而且导致了一种快... 详细信息

本文报道了基于空间滤波法对变加速运动物体表面运动速度进行实时测量的实验研究。采用 CCD线阵同时作为空间滤波器和光电转换器件。由 CCD线阵实现的差分栅式空间滤波器不仅消除了零频分量对低速运动测量的不利影响 ,而且导致了一种快速动态累加采样方法。实验结果表明 ,这一方法可对变加速物体运动速度进行实时测量。

关键词： CCD线矩空间滤波器光栅运动速度检测

QUANTUM EULER-POISSON SYSTEM： LOCAL EXISTENCE OF SOLUTIONS

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Journal of Partial Differential Equations 2003年第4期16卷 306-320页

作者： HaoChengchun JiaYueling LiHailiang AcademyofMathematicsandSystemSciences CASBeijing100080China institutfürMathematik UniversitaetWienA-1090Austria

The one-dimensional transient quantum Euler-Poisson system for semiconductors is studied in a bounded interval. The quantum correction can be interpreted as a dispersive regularization of the classical hydrodynamic equations and mechanical effects. The existence and uniqueness of local-in-time solutions are proved with lower regularity and without the restriction on the smallness of velocity, where the pressure-density is general (can be non-convex or non-monotone).

关键词：量子EULER-POISSON系统局部存在性半导体经典解波动方程

Influence of Chiral Mean Field on Kaon In-plane Flow in Heavy Ion Collisions

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Communications in Theoretical Physics 2004年第5期41卷 746-750页

作者： ZHENGYu-Ming FUCHSChristian FAESSLERAmand SHEKHTERKirril SRISAWADPornrad KOBDAJChinorat YANYu-Peng ChinaInstituteofAtomicEnergy P.O.Box275（18）Beijing102413China 4institutfǖrTheoretischePhysikderUniversitātTǖbingen D-72076TǖbingenGermany SchoolofPhysics SuranarreUniversityofTechnologyNakhonRatchasima30000Thailand

The influence of the chiral mean field on the in-plane flow in heavy ion collisions at SIS energy is investigated within covariant kaon dynamics. For the kaon mesons inside the nuclear medium a quasi-particle picture including scalar and vector fields is adopted and compared to the standard treatment with a static potential. It is confirmed that a Lorentz force from spatial component of the vector field provides an important contribution to the in-medium kaon dynamics and strongly counterbalances the influence of the vector potential on the in-plane flow. The calculated results show that the new FOPI data can be reasonably described using the Brown & Rho parametrization, which partly takes into account the correction of higher order contributions in the chiral expansion. This indicates that one can abstract the information on the kaon potential in a nuclear medium from the analysis of the in-plane flow.

关键词： kaon in-plane flow kaon mean field covariant kaon dynamics heavy ion collision